Coating with metal marking resistance

ABSTRACT

A coating composition having excellent durability and resistance to metal marking. The coating composition includes a binder system comprising at least a first resin component, optionally, one or more other resin components, a crosslinking component and a texture-producing component. Coated articles with the coating composition applied to at least a portion of a surface thereof are also provided.

CROSS REFERENCE TO RELATED APPLICATION(S)

This international application claims priority from U.S. ProvisionalApplication No. 62/281,388, filed 21 Jan. 2016, and entitled “Coatingwith Metal Marking Resistance,” and U.S. Provisional Application No.62/281,327, filed 21 Jan. 2016, and entitled “High Reflectance Coating,”each of which is incorporated by reference herein in its entirety.

BACKGROUND

Polymer coating compositions are routinely applied to substrates,especially metal substrates. Such coatings are used for a variety ofreasons, including, for example, to protect the substrate fromdegradation, to beautify the substrate (e.g., to provide color,brightness, etc.), and/or to reflect light.

Many such polymer coating compositions are applied on planar substrates(e.g., using coil coating processes) that are subsequently formed intofinished articles, including articles used as exterior buildingmaterials, for light fixtures, and the like. The coating must alsomaintain a suitable aesthetic appearance (gloss, color, and the like)over prolonged periods of exposure to various conditions, includinglight, humidity, rain, fluctuating temperatures, and the like.

During fabrication, coil coated parts may incur incidental marks orother surface defects through contact with other metal parts orsurfaces. The finished product then will have a marred appearance andmay need to be cleaned. Moreover, in some cases, these surface marks areso numerous and frequent that the part cannot be effectively cleaned orused and must be scrapped, leading to material waste and increased cost.

Accordingly, there is a continuing need for coil coatings that resistmarking by metal and thereby reduce cleaning and maintenance costsassociated with coil coated parts and articles.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a photographic comparison of panels coated with coatingcompositions having high gloss, low gloss, and very low gloss.

SUMMARY

In one embodiment, the present description provides a cured coatingformed from a coating composition that forms demonstrates resistance tometal marking when cured. The coating composition includes a bindersystem that comprises at least a first binder resin component. Thecoating composition may include other ingredients, including one or moreof the following: (i) a crosslinking agent, (ii) a catalyst, (iii)pigments, and/or (iv) a texture-producing additive, and/or (v) a flowagent, among other components. The composition forms a low gloss coatingwith a 60° gloss rating of about 5, and does not show appreciablemarking, marring or other surface defects caused by incidental contactwith other metal surfaces.

In another embodiment, the present description provides coated articles,typically metal substrates, having disposed on at least a portion of thesubstrate a cured coating formed from the coating composition describedherein.

In yet another embodiment, the present invention provides a method ofproducing an article from a metal substrate, wherein the substrate has,disposed on at least a portion of its surface, a cured coating formedfrom the coating composition described herein.

Definitions

Unless otherwise specified, the following terms as used herein have themeanings provided below.

Substitution is anticipated on the organic groups of the polyesters andother polymeric resins used in the coating compositions describedherein. As a means of simplifying the discussion and recitation ofcertain terminology used throughout this application, the terms “group”and “moiety” are used to differentiate between chemical species thatallow for substitution or that may be substituted and those that do notallow or may not be so substituted. Thus, when the term “group” is usedto describe a chemical substituent, the described chemical materialincludes the unsubstituted group and that group with O, N, Si, or Satoms, for example, in the chain (as in an alkoxy group) as well ascarbonyl groups or other conventional substitution. Where the term“moiety” is used to describe a chemical compound or substituent, only anunsubstituted chemical material is intended to be included. For example,the phrase “alkyl group” is intended to include not only pure open chainsaturated hydrocarbon alkyl substituents, such as methyl, ethyl, propyl,t-butyl, and the like, but also alkyl substituents bearing furthersubstituents known in the art, such as hydroxy, alkoxy, alkylsulfonyl,halogen atoms, cyano, nitro, amino, carboxyl, etc. Thus, “alkyl group”includes ether groups, haloalkyls, nitroalkyls, carboxyalkyls,hydroxyalkyls, sulfoalkyls, etc. On the other hand, the phrase “alkylmoiety” is limited to the inclusion of only pure open chain saturatedhydrocarbon alkyl substituents, such as methyl, ethyl, propyl, t-butyl,and the like. The term “hydrocarbyl moiety” refers to unsubstitutedorganic moieties containing only hydrogen and carbon. As used herein,the term “group” is intended to be a recitation of both the particularmoiety, as well as a recitation of the broader class of substituted andunsubstituted structures that includes the moiety.

The term “crosslinker” refers to a molecule capable of forming acovalent linkage between polymers or between two different regions ofthe same polymer.

The term “on”, when used in the context of a coating applied on asurface or substrate, includes both coatings applied directly orindirectly to the surface or substrate. Thus, for example, a coatingapplied to a primer layer overlying a substrate constitutes a coatingapplied on the substrate.

Unless otherwise indicated, the term “polymer” includes bothhomopolymers and copolymers (i.e., polymers of two or more differentmonomers). Similarly, unless otherwise indicated, the use of a termdesignating a polymer class such as, for example, “polyester” isintended to include both homopolymers and copolymers (e.g.,polyester-urethane polymers).

The term “unsaturation” when used in the context of a compound refers toa compound that includes at least one double bond that is not present inan aromatic ring.

As used herein, the term “silicone” refers to polymerized siloxanes orpolysiloxanes, which are mixed inorganic-organic polymers with thegeneral structural formula [R₂SiO]n, where R is substituted orunsubstituted C1-C12 alkyl, C1-C12 alkoxy, C6-C10 aryl, and the like. Asused herein, the silicone is a hydroxy-functional or alkoxy-functionalpolysiloxane.

The term “metal marking” as used herein refers to the marks, scratches,or other defects incurred by a coated article or surface as a result ofcontact with other (typically bare) metal surfaces or articles. Thesemarks are usually black or gray, and white and/or light-colored coilcoatings are more susceptible to metal marking than dark-coloredcoatings. Metal marking tends to occur most frequently during forming orfabrication processes.

“Soft touch” or “soft to the touch,” as used herein refers to a coatedsurface with a low gloss velvet-like appearance that simulates the senseof touch. The terms are used interchangeably herein with the term“tactile” or “tactile feel.”

The term “comprises” and variations thereof do not have a limitingmeaning where these terms appear in the description and claims.

The terms “preferred” and “preferably” refer to embodiments of theinvention that may afford certain benefits, under certain circumstances.However, other embodiments may also be preferred, under the same orother circumstances. Furthermore, the recitation of one or morepreferred embodiments does not imply that other embodiments are notuseful, and is not intended to exclude other embodiments from the scopeof the invention.

As used herein, “a,” “an,” “the,” “at least one,” and “one or more” areused interchangeably. Thus, for example, a coating composition thatcomprises “an” additive can be interpreted to mean that the coatingcomposition includes “one or more” additives.

Also herein, the recitations of numerical ranges by endpoints includeall numbers subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2,2.75, 3, 3.80, 4, 5, etc.). Furthermore, disclosure of a range includesdisclosure of all subranges included within the broader range (e.g., 1to 5 discloses 1 to 4, 1.5 to 4.5, 1 to 2, etc.).

DETAILED DESCRIPTION

In one embodiment, the present description provides a cured coatingformed from a thermosetting coating composition that exhibits excellentresistance to metal marking. The coating composition typically comprisesa binder system, a crosslinking agent, a catalyst, a flow agent, one ormore pigments, and an optional liquid carrier, along with a texturingadditive. The binder system preferably includes at least a first resincomponent, and optionally, one or more additional resin components.Preferably, the coating composition includes at least a film-formingamount of the binder system. Although coating compositions including aliquid carrier are presently preferred, it is contemplated that thecomposition described herein may have utility in other coatingapplication techniques such as, for example, powder coating, extrusion,or lamination.

The binder system described herein includes at least a first resincomponent. The first resin component is preferably a polyester resin,more preferably a durable polyester resin. Suitable polyesters include,for example, resins formed by reaction of compounds having reactivefunctional groups such as, for example, compounds with hydroxyl,carboxyl, anhydride, acyl, or ester functional groups. Hydroxylfunctional groups are known to react, under proper conditions, withacid, anhydride, acyl or ester functional groups to form a polyesterlinkage. Suitable compounds for use in forming the polyester resininclude mono-, di-, and multi-functional compounds. Di-functionalcompounds are presently preferred. Suitable compounds include compoundshaving reactive functional groups of a single type (e.g., mono-, di-, orpoly-functional alcohols or mono-, di-, or poly-functional acids) aswell as compounds having two or more different types of functionalgroups (e.g., a compound having both an anhydride and an acid group, ora compound having both an alcohol and an acid group, etc.). The bindersystem may include one or more additional resin components that are thesame as, or different from, the first resin component.

In an embodiment, the binder system includes a second polyester resincomponent in addition to the first resin component. The second polyesterresin component is preferably a silicone-modified or siliconizedpolyester resin. Suitable siliconized polyesters include those formed bythe reaction of silicone-functional compounds with compounds havingother reactive functional groups such as, for example, compounds withhydroxyl, carboxyl, anhydride, acyl, or ester functional groups.Suitable silicone-functional compounds include, for example, polymerizedsiloxanes (also known as organo-siloxanes or organic polysiloxanes) ofthe general formula [R₂SiO]_(n), where R is typically C1-C12 alkyl(preferably methyl or ethyl), C1-C12 alkoxy (preferably methoxy orethoxy), aryl (preferably phenyl), and the like. In an aspect, thepolymerized siloxanes include reactive functional groups, such ashydroxyl groups, alkoxy groups, silanol groups, and the like. Preferredsiliconized polyesters as used herein are further described inApplicants' co-pending international application, PCT/US2014/070096,filed Jan. 9, 2015.

If the binder system described herein includes siliconized polyester,the amount of siliconized polyester is preferably about 5 to 60 wt %,more preferably about 10 to 55 wt %, based on the total weight of thebinder system.

The amount of the binder system in the coating composition describedherein is preferably about 1 to 65 wt %, more preferably about 15 to 50wt %, and most preferably about 20 to 40 wt %, based on the total weightof the coating composition. The amount of binder used in the compositionwill vary depending on the resin component(s) selected.

In an embodiment, the coating composition further includes a crosslinkeror crosslinking agent. The crosslinker may be used to facilitate cure ofthe coating and to build desired physical properties. When present, theamount of crosslinker will vary depending upon a variety of factors,including, e.g., the intended end use and the type of crosslinker.Typically, one or more crosslinkers will be present in the coatingcomposition in an amount greater than about 0.01 wt-%, more preferablyfrom about 5 wt % to about 50 wt %, even more preferably from about 10wt % to about 30 wt %, and most from about 15 wt % to about 20 wt %,based on total weight of resin solids.

Polyesters having hydroxyl groups are curable through the hydroxylgroups. Suitable hydroxyl-reactive crosslinking agents may include, forexample, aminoplasts, which are typically oligomers that are thereaction products of aldehydes, particularly formaldehyde; amino- oramido-group-carrying substances exemplified by melamine, urea,dicyandiamide, benzoguanamine and glycoluril; blocked isocyanates, or acombination thereof.

Suitable crosslinkers include aminoplasts, which are modified withalkanols having from one to four carbon atoms. It is suitable in manyinstances to employ precursors of aminoplasts such as hexamethylolmelamine, dimethylol urea, hexamethoxymethyl melamine, and theetherified forms of the others. Thus, a wide variety of commerciallyavailable aminoplasts and their precursors can be used. Suitablecommercial amino crosslinking agents include those sold by Cytek underthe tradename CYMEL (e.g., CYMEL 301, CYMEL 303, and CYMEL 385 alkylatedmelamine-formaldehyde resins, or mixtures of such resins, are useful) orby Solutia under the tradename RESIMENE.

Suitable crosslinkers may also include blocked isocyanates, such as, forexample, as described in U.S. Pat. No. 5,246,557. Blocked isocyanatesare isocyanates in which the isocyanate groups have reacted with aprotecting or blocking agent to form a derivative that will dissociateon heating to remove the protecting or blocking agent and release thereactive isocyanate group. Some examples of suitable blocking agents forpolyisocyanates include aliphatic, cycloaliphatic or aralkyl monohydricalcohols, hydroxylamines and ketoximes. Presently preferred blockedpolyisocyanates dissociate at temperatures of around 160° C. Thepresence of a catalyst is preferred to increase the rate of reactionbetween the liberated polyisocyanate and the active hydrogen-containingcompound (e.g., a hydroxyl-functional polyester). The catalyst can beany suitable catalyst such as, for example, dibutyl tin dilaurate ortriethylene diamine.

Suitable crosslinkers also include unblocked isocyanates. Unblockedisocyanates are difunctional or polyfunctional isocyanates with freeisocyanate groups attached to aliphatic, cycloaliphatic, aryl,araliphatic and/or aromatic moieties. Examples include, withoutlimitation, tetramethylene diisocyanate, hexamethylene diisocyanate,dodecamethylene diisocyanate, 1,4-diisocyanatocyclohexane,3,5,5-trimethylcyclohexyl isocyanate, isophorone diisocyanate, and thelike.

In some embodiments, an ultraviolet curing crosslinker or anelectron-beam curing crosslinker may be suitable. Examples of suitablesuch crosslinkers may include 1,6-hexanediol diacrylate, 1,4-butanedioldiacrylate, trimethylolpropane triacrylate, or mixtures thereof.

The coating composition described herein may be produced by conventionalmethods known to those of skill in the art. In an embodiment, thecoating composition is prepared by use of a polymerization or processingaid, such as a catalyst, for example. Suitable processing aids include,without limitation, metal catalysts (e.g., stannous oxalate, stannouschloride, butylstannoic acid, dibutyl tin oxide, tetrabutyltitanate, ortetra butylzirconate), antioxidants (e.g., hydroquinone,monotertiarybutyl-hydroquinone, benzoquinone,1,4-napthoquinone,2,5-diphenyl-p-benzoquinone, or p-tertbutylpyrocatechol), unblocked and blocked acid catalysts (e.g.,dinonylnaphthalene sulfonic acid, dinonylnaphthalene disulfonic acid,dodecyl benzene sulfonic acid, p-toluene sulfonic acid, phosphateesters, and mixtures or combinations thereof), and mixtures thereof. Theamount of catalyst depends on the amount and nature of the reactants,but is up to about 5 wt %, preferably up to about 2 wt %, based on thetotal weight of resin solids.

In an embodiment, the coating composition described herein includes oneor more pigments. In an aspect, the pigment is preferably dispersed inthe siliconized polyester component or in the melamine crosslinkingagent. In another aspect, commercially available tint pastes may be usedor combined with other pigments and incorporated into the coatingcomposition to achieve the desired color or shade.

In an embodiment, the pigment may be dispersed in a blending polymer.Blending polymers include, for example, saturated polyesters, aliphaticpolyurethane dispersions, and the like. In an aspect, the blending resinhas a larger particle size and lower cost than either the firstpolyester resin or the siliconized polyester, and may be used as apartial replacement for the first polyester resin, or to influencespecific coating properties such as, for example, flexibility.

In some embodiments, the pigment:binder weight ratio of the coatingcomposition is preferably at least 0.02:1 to about 1.4:1. In certainembodiments, the pigment:binder weight ratio does not exceed about1.4:1.

Other additives known in the art, may be included in the coatingcomposition described herein. These additives include, withoutlimitation, flatting agents, flow or viscosity modifiers,texture-providing additives, waxes and/or other binders that may beincluded or dispersed in the coating composition.

In an embodiment, the coating described herein is a very low glosscoating. Such low gloss coatings are useful as they cover imperfectionson substrate surfaces better than coatings with higher gloss, providingsignificant advantages during fabrication. In a preferred aspect, acured coating formed from the composition described herein demonstratesspecular 60° gloss (as measured by a handheld gloss meter) of about 10,preferably 1 to 5, more preferably, less than 5.

Conventionally, low gloss coatings are prepared by including one or moreflatting agents in the coating composition. Suitable flatting agentsinclude, for example, silica, silica-based materials, or other materialswith particles known to provide easy dispensability. The amount offlatting agent depends on the desired gloss or reflectivity of the curedcoating. A typical low gloss coating composition may include up to about6 wt %, preferably 1 to 5 wt %, of a silica or silica-based flattingagent, based on the total weight of resin solids in the composition.

However, to produce coatings with 60° gloss as low as described herein,i.e. preferably less than 5, a coating composition would have to includea significant excess of flatting agent, and at such high flatting agentlevels, the beneficial mechanical properties of the composition would belost.

Surprisingly, the composition described herein demonstrates very low 60°gloss, but does not include a significant excess of flatting agent andshows no loss in beneficial mechanical properties. In an embodiment, thecompositions described herein produce very low gloss cured coating as aresult of forming a microtextured or microwrinkled surface topography.Without limiting to theory, this microwrinkled surface topography isbelieved to cause diffused reflection as a result of light scatteringand sub scattering from the irregular surface of the coating.

To form a microtextured or microwrinkled coating surface, the coatingcomposition described herein includes a texture-producing additiveintended to produce a microwrinkled surface when the coating is cured.Accordingly, in an embodiment, the coating composition described hereinincludes an amine additive to produce the microwrinkled surfacetopography. Without limiting to theory, it is believed that the aminetends to volatilize as the coating composition is cured and surfacewrinkles are formed as a result.

In an embodiment, the texture-producing additive is an amine having thegeneral formula (I):

NR¹R²R³   (I)

In formula (I) R′, R², and R³ may each independently be H; unsubstitutedC1-C10 alkyl; substituted C1-C10 alkyl, wherein the substituents includeC1-C10 alkyl, alkenyl, aryl, halide, hydroxyl, and the like;unsubstituted and substituted C4-C10 branched alkyl; unsubstituted aryl;substituted aryl, wherein the substituents include C1-C10 alkyl,alkenyl, aryl, halide, hydroxyl, and the like; C1-C10 ketone; C1-C10aldehyde; C1-C10 ether; aryl ketone; aryl aldehyde; aryl ether; and thelike, and mixtures or combinations thereof.

In an embodiment, the coating composition described herein includes theamine additive in an amount of preferably about 0.001 to 5 wt %, morepreferably 0.1 to 2 wt %, based on the total weight of the composition.

In an embodiment, the coating composition described herein includes oneor more flow modifiers. These flow or viscosity modifiers are typicallyused to aid in air release and improve the flow of the composition toallow for application to a substrate. Suitable flow modifiers include,for example, silicone-based compounds, metal salts of aromaticcarboxylic acids (e.g., unsubstituted salicylic acid, unsubstitutednaphthoic acid, alkyl- or aralkyl-substituted salicylic acid, alkyl- oraralkyl-substituted naphthoic acid, and the like), metal salts ofaromatic hydroxy-functional carboxylic acids (e.g.,2-hydroxy-3-naphthoic acid, alkyl-substituted 2-hydroxy-3-naphthoicacid, and the like), and the like. In a preferred aspect, the flowmodifier is a silicone-based compound and is present in an amount ofabout 1 wt %, preferably 0.01 to 0.5 wt %, based on the total weight ofresin solids in the composition.

In an embodiment, the coating composition described herein includes oneor more waxes. The wax is typically used to aid in handling of thecoating composition prior to application, and may also be used to reduceor prevent abrasion of the cured coating. Suitable waxes include, forexample, naturally occurring waxes (e.g., carnauba and the like),polymeric waxes (e.g., polyethylene-polyvinyl acetate wax, polyethyleneglycol wax, and the like), etc. In a preferred aspect, the coatingcomposition described herein includes a polymeric was, such as PTFE waxor polyethylene wax, and the wax is present in amount of up to about 15wt %, preferably about 1.5 to 10 wt %, based on the total weight ofresin solids in the composition.

The total amount of solids present in the coating composition describedherein may vary depending upon a variety of factors including, forexample, the desired method of application. For coil coatingapplications, the coating composition will typically include from about30 to about 65 wt % of solids. In some embodiments, the coatingcomposition may include as much as 80 wt % or more of solids.

Preferred cured coating compositions of the invention have excellentadhesion, hardness, flexibility, and demonstrate resistance to metalmarking. The combined properties of low gloss and improved resistance tometal marking provide a significant advantage over existing technologies, particularly in reducing the amount of finished parts that must bescrapped after fabrication.

During fabrication of a coil coated article, the article may incurincidental marks from contact with bare metal from other parts orsurfaces involved in coil coating. These marks may be numerous enough orpresent in locations that render the article unusable. As a result, thecoated article has to be scrapped. Using a coating that reduces theoccurrence of these marks and/or hides the appearance of these markswill reduce the amount of scrap and off-grade products or articlesgenerated during the fabrication process.

Similarly, during regular use of a coated article, the article may comeinto contact with bare metal resulting in the transfer of marks to thecoated surface of the article. The article then takes on a marred ordamaged appearance and has to be cleaned. Therefore, a coating thereduces the occurrence and appearance of such marks will reduce the costand maintenance costs associated with coil coated articles, and willallow coated article to retain a fresh, new appearance for a longerperiod of time.

The coating composition described herein, when applied to a substrateand cured, preferably demonstrates durability and improved resistance tometal marking relative to commercially available coil coatings. Withoutlimiting to theory, this is believed to be a result of the microwrinkledsurface topography of the coating. This leads to a reduction in thenumber of marks or color transferred to the coated surface, and anoverall reduction in fabrication and processing costs.

In addition to durability and resistance to metal marking, the curedcoating described herein may also demonstrate other useful performancecharacteristics such as, for example, pencil hardness, flexibility, highreflectance, and the like.

In an embodiment, the coating composition described herein provides acured coating with a soft touch or tactile feel. Without limiting totheory, the microwrinkled or microtextured surface topography provides avery low gloss surface that simulates the sense of touch.

The coating composition described herein may be applied by a variety ofmethods known to those of skill in the art. In an embodiment, thecomposition is applied to planar metal surfaces using a coil coatingprocess. The coating is preferably applied as a thin film, withthickness in the range of preferably 0.1 to 5 mil, more preferably 0.5to 2 mil.

The coating composition has utility in a multitude of applications. Thecoating composition of the invention may be applied, for example, as anintermediate coat, as a topcoat, or any combination thereof. The coatingcomposition may be applied to sheet metal such as is used for lightingfixtures, architectural metal skins (e.g., gutter stock, window blinds,siding and window frames and the like) by spraying, dipping, orbrushing, but is particularly suited for a coil coating operation wherethe composition is applied onto the sheet as it unwinds from a coil andthen baked as the sheet travels toward an uptake coil winder. It isfurther contemplated that the coating composition of the invention mayhave utility in a variety of other end uses, including, industrialcoating applications such as, e.g., appliance coatings; packagingcoating applications; interior or exterior steel building products; HVACapplications; agricultural metal products; wood coatings; etc. In apreferred aspect, the cured coating described herein is used as anexterior coating for building materials, architectural skins and thelike.

Non-limiting examples of metal substrates that may benefit from having acoating composition of the invention applied on a surface thereofinclude hot-rolled steel, cold-rolled steel, hot-dip galvanized,electro-galvanized, aluminum, tin plate, various grades of stainlesssteel, and aluminum-zinc alloy coated sheet steel (e.g., GALVALUME sheetsteel).

The coating is typically cured or hardened in a heated temperatureenvironment of from about 200 to 500° C., more preferably from about 270to 470° C. For coil coating operations, the coating is typically bakedfor 8 to 25 seconds, to a peak metal temperature (PMT) of from about 200to 250° C.

EXAMPLES

The present invention is illustrated by the following examples. It is tobe understood that the particular examples, materials, amounts, andprocedures are to be interpreted broadly in accordance with the scopeand spirit of the invention as set forth herein. Unless otherwiseindicated, all parts and percentages are by weight and all molecularweights are weight average molecular weight. Unless otherwise specified,all chemicals used are commercially available from, for example,Sigma-Aldrich, St. Louis, Mo.

Example 1 Preparation of Coating Compositions

Coating compositions (#1 through #3) as shown in Table 1 were preparedby combining a binder system including a polyester resin with a melaminecuring agent. The resin and crosslinking agent were blended togetherusing standard mixing techniques known in the art, along with minimumlevels of flow agents to facilitate air release during the coil coatingprocess. A flatting agent is included to provide either high gloss(coating #1) or low gloss (coating #2), with gloss measured at a 60°angle with a handheld gloss meter (Byk Gardener). For coating #3, atexture-providing amine additive is included to produce a very low glosscoating. The coating compositions were combined with one or morepigments to produce coatings as shown in Table 1. The coatingcompositions were applied to metal panels using standard applicationmethods, and baked at peak metal temperatures of about 200° to 250° C.

TABLE 1 Coating Compositions Coating Gloss 1 High 2 Low 3 Very low

Example 2 Performance Testing Resistance to Metal Marking

The coating compositions of Example 1 were applied to test panels,baked, and subjected to contact with a metal marker. The panels werethen viewed under a microscope and images were generated as shown inFIG. 1. Distinct metal marks could be seen on the panels having highgloss and low gloss coatings, with the color of the mark more pronouncedin the low gloss coating. In contrast, no distinct metal marks or colortransfer are observed with the very low gloss coating and only a smallchange in surface appearance is seen when viewed under greatermagnification.

Having thus described the preferred embodiments of the presentinvention, those of skill in the art will readily appreciate that theteachings found herein may be applied to yet other embodiments withinthe scope of the claims hereto attached. The complete disclosure of allpatents, patent documents, and publications are incorporated herein byreference as if individually incorporated.

1. A coated article comprising a substrate; and a cured coating disposedon the substrate, wherein the cured coating is derived from a coatingcomposition comprising: a binder resin system comprising at least afirst resin component; a crosslinking component; and a texture-producingcomponent, wherein the cured coating demonstrates resistance to metalmarking.
 2. (canceled)
 3. The article of claim 1, wherein the firstresin component is a polyester resin.
 4. The article of claim 1, whereinthe binder resin component further includes a second resin componentcomprising a silicon-modified polyester resin.
 5. The article of claim1, wherein the crosslinking component is a hydroxyl-reactivecrosslinker.
 6. The article of claim 1, wherein the crosslinkingcomponent is an amine-functional crosslinker.
 7. The article of claim 1,wherein the crosslinking component is selected from an aminoplast, anamino- or amido-group carrying substance, a blocked isocyanate, or acombination thereof.
 8. The article of claim 1, wherein thetexture-producing component is an amine of the general formula NR¹R²R³,wherein R1, R2 and R3 are each independently H, C1-C10 alkyl, branchedC4-C10 alkyl, hydroxyl-substituted C1-C10 alkyl, hydroxyl-substitutedbranched C4-C10 alkyl, phenyl, or substituted phenyl.
 9. The article ofclaim 1, wherein the article is selected from metal structures, metalbuilding products, household appliances, and combinations thereof. 10.The article of claim 1, wherein the coating composition is applied tothe substrate at a film thickness of about 0.5 to 2 mil.
 11. (canceled)12. The article of claim 1, wherein the cured coating formed from thecomposition has 60° gloss of about
 5. 13. The article of claim 1,wherein the cured coating formed from the composition has 60° gloss ofless than about
 5. 14. The article of claim 1, wherein thetexture-producing component is present in an amount of about 0.001 to 5weight percent, based on the total weight of the coating composition.15. The article of claim 1, wherein the coating composition includes upto about 5 wt % flatting agent.
 16. The article of claim 1, wherein thebinder resin component is present in an amount of about 1 to 65 weightpercent, based on the total weight of the composition.